Improvement in amalgamators



w. ALKER,

AMALGAMA-TOR.

Patented May 29,1877.

N-PETERS, PHOTO-UTNOGRAPHER. WASHINGTON. D. C.

THOMAS WALKER, 0F PHILADELPHIA, PA., AssIeNoR ro THOMAS WALKER,

JOSEPH W. BANGROFT, AND s.

H. SAFFORD, OF SAME PLACE.

IMPROVEMENT IN AMALGAMATORS.

Specification forming part of Letters Patent No. 191,272, dated May 29,1877; application filed September 18, 1876.

To all whom it may concern:

Be it known that I, THOMAS WALKER, of Philadelphia. Pennsylvania, haveinvented certain Improvements in Amalgamators, of which the following isa specification:

My invention relates to certain improvements in the amalgamator forwhich Letters Patent were granted to J. W. Bancroft; and myself on the23d day of November, 1875; the objects of my invention being to preventthe hot air which accumulates in the apparatus from interfering with thecharging operation, and to provide an efficient device for cooling theore as it passes from the apparatus.

These objects I attain in the manner which I will now proceed todescribe, reference being bad to the accompanying drawing, in which-Figure 1 is a vertical section of my improved amalgamator; Fig. 2, aside view, partly in section; and Fig. 3, an enlarged sectional view ofa portion of the same.

I will briefly describe, in the outset, the above-mentioned patentedamalgamator, reference being had to Fig. 1 of the drawing.

A vertical retort, A, is arranged within a furnace, B, having flues ofsuch a character that the products of combustion, in passing from thefire-place to the chimney, are caused to take a circuitous coursearound, and in contact with, the retort, which becomes highly heated.

The upper portion of the retort projects above the top of the furnace,and into this portion of the retort the ore is fed through a suitablehopper, D, the charge resting upon a valve, a, Where it is subjected tothe vapor arising from mercury previously introduced into the cup-shapedvalve 1). After being subjected to this preliminary treatment for aproper length of time, the ore is dumped directly into the valve 1), andis there subjected to the full efl'ect of the mercury vapor, a freshsupply being placed upon the valve a. As the mercury vapor comes incontact with the cold ore in the top of the retort it is condensed, anddescends until it is again vaporized.

After the ore on the valve 1) has been sufficiently heated it is dumpedinto an extension of the retort, where it is permitted to become cool.

In the Bancroft and Walker patent this extension was inclined, and theore was permitted to pass gradually down the same; but this plan hasbeen found to be objectionable in practice, partly on accountof thespace which the extension occupied, and partly because the cooling ofthe ore was not as expeditious as is desirable.

In place of this inclined extension I make an extension, A, at rightangles, or thereabout, to the retort A, and communicating therewith at apoint below the valve b.

In this extension I place a screw, d, which removes the ore from thelower portion of the retort A, and delivers it at the outlet E. I makethe walls of this extension double, with an intervening annular chamber,e, through which cold air or water is caused to circulate, thus formingan air or water jacket around the ore-passage, for it has been found inpractice that the bringing of water into direct contact with the ore atthis point causes the generation of vapor, which ascends into andinterferes with the operation of the retort A.

The charging of the above-mentioned patented apparatus was also attendedwith some difficulty, owing to the fact that the air contained in thecharge became expanded by heat, so that when the upper portion of theretort was opened to introduce a new charge the expanded air escaped inpufl's, and scattered the ore just introduced.

This objection I overcome by providing the upper portion of the retort Awith a porous section, F, which allows the air to escape as it expands,and thus prevents the creation of a detrimental pressure in this portionof the retort.

The hopper D has, in the present instance, a tubular shaft, H, which isprovided with two slides, f and f, so that the quantity of each chargecan be determined, and so that the upper slidefcan be closed before thelower slide f is opened, thereby preventing the escape of gases at thispoint.

In order to prevent the escape of the mercury vapor, the tubes g,through which the PATENT OFFICE. f

stems i of the valves a and b pass, are pro-- vided at their outer ends,which project beyond the walls of the furnace, with stuflingboxes I,packed with asbestos, or other material not injuriously affected byheat; and in order to still further prevent the chance of escape'ot' themercury vapor, [prefer to form on each valve-stem '5 a collar, m,adapted to a ground seat in the end of the tube g, as shown in Fig. 3.

I claim as my invention- 1. The retort A, provided at or near its up perend with a porous section, F, as set forth.

2. The combination of the retort A with the annular extension A, havingdouble walls, formingan annular chamber, a, and with means,substantially as described, for conveyin g the ore through thisextension, as set forth In testimony whereof I have signed my name tothis specification in the presence of two subscribing; witnesses.

THOS. WALKER.

Witnesses:

HENRY HOWSON, Jr., HARRY. SMITH.

